11-21-04 12:45 PM
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Thomas J. Boschloo wrote:
| Thanks for the clarification. I was under the assumption that Reliable
| 'outsourced' its mixmaster traffic to the mixmaster executable.. I was
| wrong.
|
| OTOH, this can be very worrying to users of reliable as I have seen code
| (posted by Richard some years ago) that Reliable used the standard
| Visual Basic RNG for ESub instead of sound cryptographically strong
| random functions! I wouldn't trust RProcess of doing sound cryptography
| from what limited code I have seen from him.. If the seed of the VB
| rand() function is known, an attacker could perhaps predict the order in
| which messages leave the remailer <scarry thought>.
Since I wrote this, I have had some more time to think about it. Since
the ESub function in Reliable uses Visual Basic's standard (non-crypto)
random function, an attacker can, by sending an ESub message, get the 64
bits that are randomized and search for the seed which results in these
64 bits to get selected.
This seems very bad to me. It is worse than using random functions on
its own since the attacker can see the output of the rand() function.
How should this be solved then? My guess is that all uses of the rand()
function in Reliable should be replaced by its secure counterparts. I am
sure someone with good knowledge of Visual Basic could access the
cryptographically sound random functions in Windows that perhaps,
RProcess didn't have access to at the time...
| | You do understand that Reliable latency is a random time between a
| | Minimum and Maximum latency configured by the operator.
|
| That doesn't seem like a good idea to me at all! Even Minimum latency
| seems like a design flaw to me..
Also having spend more time thinking on this, the range of latency that
a message in Reliable will have will be limited between the Min and Max
latency settings set by the operator. A solution would be to set the
Minimum latency to 0 seconds and the Maximum latency to something like
three days.
Highest esteems,
Thomas J.
- --
The Thraddash: "So, what's this? SNORT! An unknown alien species?"
"How wonderful! Someone new to fight!"
Full Game Win/Mac/Linux: <http://sc2.sourceforge.net>
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